1. Field of the Invention
The present invention relates to a key interlock system of a vehicle equipped with an automatic transmission, which has a mechanical structure.
2. Description of Related Art
In general, key interlock systems of vehicles equipped with an automatic transmission should satisfy two conditions of US Federal Motor Vehicle Safety Standards 114 (FMVSS114).
The first condition is that the shift lever positioned at the P-range (Parking) can shift to other ranges (R-range, N-range, and D-range) only when the key inserted in the ignition lock cylinder is turned to ‘ON’. The second condition is that the key can be pulled out of the key hole of the ignition lock cylinder only when the shift lever is positioned at the P-range (Parking).
The key interlock systems of vehicles equipped with an automatic transmission have important functions of preventing safety accidents due to carelessness of drivers and vehicle theft.
Further, most key interlock systems of vehicles equipped with an automatic transmission, which has been widely used, electronic devices that control the operation of the ignition lock switch and key interlock switch, using a solenoid that is operated by control of an ECU (Electronic Control Unit). However, the electronic devices are expensive, make large noise in operation, and easily break down.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.